This article is full of errors:

Capone didn't plan or order the massacre. McGurn wanted it in revenge for having almost been killed by the Gusenberg brothers (and Frank wasn't a "doctor") in a phone booth. Capone agreed to it and fronted money to McGurn to set it up. McGurn and his girlfriend, Louise Rolfe, checked into a hotel on the day of the massacre, kept ordering room service and asking the front desk for the time in order to establish an alibi (she was called "the Blond Alibi"). McGurn later married her so that she couldn't be forced to testify against him. Laurence Bergreen, Capone's most recent biographer, says the killers were Fred (Killer) Burke of the Circus gang (McGurn wasn't in that gang, he was Capone's chief bodyguard), Patsy Lolordo, Albert Anselmi and John Scalise. The brouhaha and law enforcement crackdown caused by the massacre soured Capone on McGurn, who lost favor with his boss. McGurn was gunned down several years later in a bowling alley.